title: Low-loss, extreme subdiffraction photon confinement via silicon carbide localized surface phonon polariton resonators.
abstract: Plasmonics provides great promise for nanophotonic applications. However, the high optical losses inherent in metal-based plasmonic systems have limited progress. Thus, it is critical to identify alternative low-loss materials. One alternative is polar dielectrics that support surface phonon polariton (SPhP) modes, where the confinement of infrared light is aided by optical phonons. Using fabricated 6H-silicon carbide nanopillar antenna arrays, we report on the observation of subdiffraction, localized SPhP resonances. They exhibit a dipolar resonance transverse to the nanopillar axis and a monopolar resonance associated with the longitudinal axis dependent upon the SiC substrate. Both exhibit exceptionally narrow linewidths (7-24 cm(-1)), with quality factors of 40-135, which exceed the theoretical limit of plasmonic systems, with extreme subwavelength confinement of (λ(res)3/V(eff))1/3 = 50-200. Under certain conditions, the modes are Raman-active, enabling their study in the visible spectral range. These observations promise to reinvigorate research in SPhP phenomena and their use for nanophotonic applications.
authors.affiliation: US Naval Research Laboratory, Washington, DC, United States. joshua.caldwell@nrl.navy.mil
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Caldwell
authors.forename: Orest J
authors.initials: OJ
authors.lastname: Glembocki
authors.forename: Yan
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authors.lastname: Francescato
authors.forename: Nicholas
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authors.lastname: Sharac
authors.forename: Vincenzo
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authors.lastname: Giannini
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Bezares
authors.forename: James P
authors.initials: JP
authors.lastname: Long
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Owrutsky
authors.forename: Igor
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authors.lastname: Vurgaftman
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Tischler
authors.forename: Virginia D
authors.initials: VD
authors.lastname: Wheeler
authors.forename: Nabil D
authors.initials: ND
authors.lastname: Bassim
authors.forename: Loretta M
authors.initials: LM
authors.lastname: Shirey
authors.forename: Richard
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authors.lastname: Kasica
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Maier